Re: [PATCH v2 6/7] vdpa/mlx5: conditionally show MTU and STATUS in config space

[Si-Wei Liu]

On 2/2/2023 5:31 AM, Eli Cohen wrote:
> On 01/02/2023 1:22, Si-Wei Liu wrote:
> > The spec says:
> >      mtu only exists if VIRTIO_NET_F_MTU is set
> >      status only exists if VIRTIO_NET_F_STATUS is set
> >
> > We should only show MTU and STATUS conditionally depending on
> > the feature bits.
> >
> > Signed-off-by: Si-Wei Liu <si-wei.liu@xxxxxxxxxx>
> > ---
> >   drivers/vdpa/mlx5/net/mlx5_vnet.c | 22 ++++++++++++++--------
> >   1 file changed, 14 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c 
> > b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > index 3a6dbbc6..3d49eae 100644
> > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > @@ -3009,6 +3009,8 @@ static int event_handler(struct notifier_block 
> > *nb, unsigned long event, void *p
> >       struct mlx5_vdpa_wq_ent *wqent;
> >         if (event == MLX5_EVENT_TYPE_PORT_CHANGE) {
> > +        if (!(ndev->mvdev.actual_features & 
> > BIT_ULL(VIRTIO_NET_F_STATUS)))
> > +            return NOTIFY_DONE;
> >           switch (eqe->sub_type) {
> >           case MLX5_PORT_CHANGE_SUBTYPE_DOWN:
> >           case MLX5_PORT_CHANGE_SUBTYPE_ACTIVE:
> > @@ -3118,16 +3120,20 @@ static int mlx5_vdpa_dev_add(struct 
> > vdpa_mgmt_dev *v_mdev, const char *name,
> >               goto err_alloc;
> >       }
> >   -    err = query_mtu(mdev, &mtu);
> > -    if (err)
> > -        goto err_alloc;
> > +    if (device_features & BIT_ULL(VIRTIO_NET_F_MTU)) {
> > +        err = query_mtu(mdev, &mtu);
> > +        if (err)
> > +            goto err_alloc;
> device_features is not defined as a local variable. It is defined in 
> the next patch.
Good catch! Will revise and post a v3.

Thanks!
-Siwei

> >   -    ndev->config.mtu = cpu_to_mlx5vdpa16(mvdev, mtu);
> > +        ndev->config.mtu = cpu_to_mlx5vdpa16(mvdev, mtu);
> > +    }
> >   -    if (get_link_state(mvdev))
> > -        ndev->config.status |= cpu_to_mlx5vdpa16(mvdev, 
> > VIRTIO_NET_S_LINK_UP);
> > -    else
> > -        ndev->config.status &= cpu_to_mlx5vdpa16(mvdev, 
> > ~VIRTIO_NET_S_LINK_UP);
> > +    if (device_features & BIT_ULL(VIRTIO_NET_F_STATUS)) {
> > +        if (get_link_state(mvdev))
> > +            ndev->config.status |= cpu_to_mlx5vdpa16(mvdev, 
> > VIRTIO_NET_S_LINK_UP);
> > +        else
> > +            ndev->config.status &= cpu_to_mlx5vdpa16(mvdev, 
> > ~VIRTIO_NET_S_LINK_UP);
> > +    }
> >         if (add_config->mask & (1 << VDPA_ATTR_DEV_NET_CFG_MACADDR)) {
> >           memcpy(ndev->config.mac, add_config->net.mac, ETH_ALEN);